Feature-flagged WiFi/MQTT capability (WITH_MQTT) that bridges
LoRa mesh packets to MQTT topics over TLS (port 443). Includes:
- WiFiManager: connection handling with AP fallback mode
- MQTTBridge: TLS-secured pub/sub with FNV-1a deduplication
- WebConfig: REST API for WiFi/MQTT settings
- Embedded web UI dashboard for configuration
Default broker: meshqt.l.supported.systems:443 (MQTTS)
Build with: pio run -e heltec_v3_mqtt
